From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from cpout1.tiscali.be (cpout1.tiscali.be [62.235.13.193]) by dsl2.external.hp.com (Postfix) with ESMTP id D3122482D for ; Mon, 14 Jul 2003 04:49:02 -0600 (MDT) Date: Mon, 14 Jul 2003 12:48:56 +0200 Message-ID: <3F0BEA8300001164@ocpmta1.freegates.net> In-Reply-To: <1058030142.2314.23.camel@fuzzy> From: "Joel Soete" Subject: RE: [parisc-linux] [PATCH] fix arbitrary limits on stack size To: "James Bottomley" , parisc-linux@parisc-linux.org MIME-Version: 1.0 Content-Type: text/plain; charset="ISO-8859-1" Sender: parisc-linux-admin@lists.parisc-linux.org Errors-To: parisc-linux-admin@lists.parisc-linux.org List-Help: List-Post: List-Subscribe: , List-Id: parisc-linux developers list List-Unsubscribe: , List-Archive: >One of the problems with the PA linux implementation is the upward >growing stack. On most architectures, the virtual process space is >divided into > > >| unmapped | exec and heap | mappings and stack | TASK_UNMAPPED_BASE >TASK_SIZE > > >The mappings grow up from the start and the stack grows down from the >end of the area. If they ever meet, the process segfaults. > >On palinux, we have an upward growing stack, so we have to size the >stack so when it reaches its ulimit, it hits the top of the area. This >means that large stack limits cut into the mappable area (and also that >we have to impose a hard limit of 1GB on the stack size otherwise the >user could remove the ability to map processes entirely by setting the >stack limit too high). > >The proposal to fix this is to start the stack growing upwards from >TASK_UNMAPPED_BASE and have the mappings grow downwards from TASK_SIZE. >This should allow us to behave in exactly the same manner as x86 and not >have an arbitrary limit on the stack size. > >The attached patch (against 2.5.70-pa1) does this, if you'd like to >comment on it or try it out. I don' t remember the historical reason of this choice but do you think it is possible to back-port it into 2.4 (it will facilitate so much the merge with upstream?) Thanks in advance for advise, Joel ------------------------------------------------------ Soldes Tiscali ADSL : 27,50 euros/mois jusque fin 2003. On s'habitue vite à payer son ADSL moins cher! Plus d'info? Cliquez ici... http://reg.tiscali.be/default.asp?lg=fr